Leak indicator



Patented `luly 7, 1925;.

' MOSn'rH0iyIrsQ1tor "mariti-Marque. llamame.. Y f

' which the following: isf a -speciticationaj My present:l invention z pertains 1to.. indi--l cat'ors, andl itcOHtemplates Vthe:r provision; oli' adevice `through the mediiunroiifwihich it:

mayfbefreadilyf andf easilyV ascertained iofrthev valve ofa pneumatic' tireafter said. tire; has been; properly ,iniiatedzzisrleakingt f The in= l ntionfurther: contemplates` the.r

'provision' .of a. device othelcharacter indieA cated. thatfis.- inexpensively constructed. .andA I so Varranged that liability;Qiforcingfthe stem; of thevalve ldownwardly. and thns:releasilng;I air from the tire is tprecluded andhenceythe device. willi lonly: indicatel the icha-racter f of an.

actual leakinoraroundthefvalive; f

Other advantageous characteristics oif'fthe:J invention` wil-l, be-,tully understood from the following description(and'claims when the same are read in connection withthedr-awfings acconipanyingvandhfonmingi-partei this specification, in which: 1 I Y Figure l is a longitudinal sectional view of my device as it appears after recording a valve leak.

Figure 2 is a similar View of a portion of the indicator and showing the manner in which the working elements are returned to their normal positions. f

Figure 3 is a detail view of the interior casing of the device showing how same appears when the valve of a pneumatic tire is working properly.

Figures 4 and 5 show the appearance of said interior when the valve has a slow or last leak.

Figure G is a detail view of the portion of my device that surrounds the valve stem.

Figures 7 and- 8 are cross-sectional views oi' the device taken in the plane indicated by lines 7 7 and 8 8 respectively of Figure 1.

Figure 8 is a view illustrating the bandV that is employed to indicate visually that a leak is present in the valve.

Similar numerals of reference designate corresponding parts in all the views of the drawings.

My novel device comprises a push-button 2l that is hollow interiorly and adapted to seat in the hollow of the push-button is a Y cork or other suitable material (not shown)` and the. said: buttonaisamountedl inthe-uppervx said V button beingv limited L in #its upward movementduez to. theturnedA end 20L thereof.l Arranged: iin-.the uppeiven'dv-fof'fthe outer :cas-

ing 1 randcdirectlyl belowy the/buttonfQl-lis a sott..v rubber, cap 1.9.-' Th'iscap is securely v retained between the inner and outer ca singg's` of 'the device and .movement dueA to leakagel of a-valvelwill movegthebuttonxll upwardly. v Sight fopenngs lfare-provide'di inthecasingfvland., surroun'dingfsaid openingerlarrange a; transparent cellluloi'dl ban-dif 18f-fa-.nd2'1 l independently .thereof/if is: a@plungeril of? y cork or other suitable lightlmaterialandsaid plungerI isf surrounded "on sits -fu-ppen end" Yrby a band. zot f paper s Qrfother# suitable-materiali that is white as i1idicated -=byg Mi-and pref# upwaifdl movement ol the s plunger 1Q willE f portion l5 to Yappear at the' Y cause lthe .red

sight fopenings." v fv Y I-n order tov hold the plunger-f upc-until eov forced downwardly-'by theflm'ovement-ofbut tonk. 2l; Ii' pmvidegftheesmalll andi extremelyV ilexible wiresirl that enten;the=-pli1nger= at one end and bearat their opposite ends against the inner surface of an interior casing la.

Arranged near the lower end of the interior casing la and below the plunger l2 is an expansionable bag l1 of extremely thin para gum. This bag ll is provided with the base l() and adapted to surround the base and retain same within the casing is an eX- pansion bag base of stiff rubber 6 while below this base is a support 5 formed after the manner of a metal washer.

Arranged within the eXtreme lower end of the device is a cylinder 7 having the opening 8 and surrounding the lower end of the cylinder 7 is valve port packing 4. The cylinder 7 communicates with the valve guide 2 having the flared mouth 3 whereby lian 'Y l2 upwardly and this will cause the red portion of the band to appear at the sight opening.

If a slow leak is presentrthe red portion will move very slowly upward and if a quick leak the passage of the red port-ion will be rapid.

Movement of the plunger 12 will also move the rubber cap 19 and button upwardly. To return' the elements of the device to their normal position it is simply necessary to press downwardly on the button.

The device is extremelysiinple and inexpensive and yetis positive in action and because of such construction the nature of leaks about a valve stem may be readily deu tected.' -f

I provide the tube 7 with a closed upper end and the side slot 8 because I find that quite frequently, especially where a fast leak is present, a large amount of grit enters the tube 7 land this arrangement baiiles grit as far as possible from entering the bag 1l which would thereby eventually impede working of the device. v

IVith an open upper end the grit would Vclog the bag l1 and foreign matter would quickly reach the bag.

Having described my invention, what I claim and desire to secure by Letters Patent l. In a leak detector, the combination of a casinghaving one end open and provided with sight openings adjacent the other end thereof, a valve guide having a flared mouth and arranged in the openend of the casing,

a tube arranged in the guide, and having a slot near its upper end, an expansionable bag secured in the casing and inclosing the upper end of the tube, packing interposed between the secured end of the bag and tube, a plunger` of cork arranged to bear against the bag, means for holding the plunger at the point yit is raised by the bag, a. band seu cured to the upper end of the plunger, a cap movable in one direc-tion by the plunger and arranged above the plunger within the casing, and a button arranged on the eXtreme upper end of the casing for moving the cap downwardly againstithe plunger.

2. In a leak detector, the combination of a casing provided with sight openings, a valve guide arranged in said casing, a tube arranged in the guide and having a slot in its side near its upper end, an expansionable bag arranged in the casing above the tube, packing interposed between the tube and casing, a plunger actuable in one direction by the bag, springsfor holding the plunger at the point it is raised by the bag, a band secured to the plunger, a cap movable by the plunger, and a button arranged on the casing for moving the cap downwardly within the casing.

In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.

y MCSE THOMPSON. 

